A Portable System to Monitor Saliva Conductivity for Dehydration Diagnosis and Kidney Healthcare

Abstract

Chronic kidney disease (CKD) has become a major issue in long-term healthcare. It is caused by recurrent kidney injury, which is possible induced by dehydration and heat stress. Therefore, it is important to access the dehydration diagnosis on fields. Conventional instruments for assessing dehydration from blood and urine samples are expensive and time-consuming. These disadvantages limit their applications in high-risk groups susceptible to kidney disease. To address this unmet need, this study presents a portable miniaturized device for dehydration diagnosis with clinical saliva samples. With co-plane coating-free gold electrodes, the dehydration diagnosis was achieved with a saliva specimen at low volumes (50–500 μL). To examine the characteristics, the developed device was assessed by using standard conductivity solutions and the examined variation was <5%. To validate the use for field applications, saliva samples were measured by the developed device and the measured results were compared with standard markers of serum osmolality (N = 30). These data indicate that the measured saliva conductivity is consistent with serum osmolality. And it shows significant difference between healthy adults and healthy farmers (p < 0.05), who typically suffer high risks of CKD. Based on this work, the proposed device and measurement offer a useful method to diagnosis dehydrations and indicate possible potential for CKD.

A Portable Biodevice to Monitor Salivary Conductivity for the Rapid Assessment of Fluid Status

“…Saliva specimens of all volunteers were collected orally at least 1 h after any intake. Saliva samples were assessed with a portable conductivity meter and a sensing probe, which were designed and fabricated as described in a previous study [ 18 ]. The miniaturized sensing electrode was placed in horizontally parallel and its sample-contact area reduced.…”

“…We recently developed a novel device for measuring saliva conductivity, which has been found to be associated with fluid status [ 18 ]. Data on saliva conductivity can be acquired immediately using a portable monitor system, which allows for a non-invasive and real-time evaluation of fluid status.…”

Molecular and physical technologies for monitoring fluid and electrolyte imbalance: A focus on cancer population

“…The limitation is that the sensor needs to be placed on the ocular surface, reflecting tear secretion, which may alter the tear fluid's osmolarity. Recently, Lu et al 93 developed a portable system to monitor saliva conductivity for real-time dehydration diagnosis, which showed more than 93% sensitivity and 80% specificity (Figure 6E). They indicate that the measured saliva conductivity is consistent with serum osmolality.…”

“…(E) Custom‐made miniaturized portable system to monitor saliva conductivity through Au microelectrode on a glass substrate (Adapted from Ref. [93]). (F) Representation of an atomic emission spectrometer combined with multivariate image analysis.…”

Recent Advances in Portable Biosensors for Biomarker Detection in Body Fluids

“…Lu et al developed a biosensor for the measurement of saliva osmolality via measurement of the conductivity of saliva samples. The sensor reports a sensitivity of 93.3% and a specificity of 80% [ 24 ]. Monitoring glucose in infants for diabetes treatment is especially challenging.…”